Dermatology is the branch of science which deals with the treatment of hair, nails and skin diseases. A dermatologist treats all kinds of skin diseases, in the widest range and some cosmetic problems of the skin, scalp, hair, and nails. Some of the most common skin diseases dermatologists treat are skin cancer, warts, fungal infections, and psoriasis and hair loss. Melanoma is the most serious disease. Dermatopathology involves the microscopic examination, description and interpretation of diagnostic assay specimens obtained from the skin. A dermato-pathologist performs microscopic observation to detect the disease.